Form, fill and seal packaging machine with bag squeezer and method

• US 5,930,983 A
• Filed: 03/04/1997
• Issued: 08/03/1999
• Est. Priority Date: 06/29/1992
• Status: Expired due to Term

• Current Assignee: Pacmac Incorporated
• Original Assignee: Pacmac Incorporated
• Inventors: Terminella, Emanuele, Terminella, Joseph, Terminella, Frank
• Primary Examiner(s): JOHNSON, LINDA B
• Application Number:
  US08/811,471
• Time in Patent Office: 882 Days
• Field of Search: 53/133.4, 53/139.2, 53/373.6, 53/412, 53/436, 53/451, 53/526, 53/551, 53/552, 53/554
• US Class Current: 53/436
• CPC Class Codes: B65B 41/16 by rollers
• CPC Class Codes: B65B 61/188 by applying or incorporating profile-strips, e.g. for reclosable bags
• CPC Class Codes: B65B 9/20 the webs being formed into tubes in situ around the filling nozzles
• CPC Class Codes: B65B 9/2007 Means for stripping or squeezing filled tubes prior to sealing to remove air or products from sealing area
• CPC Class Codes: B65B 9/2028 Rollers or belts
• CPC Class Codes: B65B 9/2042 Means for altering the cross-section of the tube filling opening prior to transversal sealing, e.g. tube spreading devices subdividing filled tubes to form two or more packages by sealing involving displacement of contents B65B9/12
• CPC Class Codes: B65B 9/213 the web having intermittent motion B65B9/22 takes precedence

Abstract

A vertical form, fill and seal packing machine and method for making recloseable bags having a safety seal exterior to a recloseable seal. The machine produces durable, substantially air-tight bags at high speed and provides for the production of different size and make of bags and different amounts and types of product in the bags. The machine includes a film drive and pinch roll pair, a pair of film pull belts, and a pair of zipper drive rollers for pulling the plastic film and zipper strip through the machine. The production of different size bags is facilitated by having the film drive roll, pull belts, and zipper drive rollers simultaneously driven in bag length increments by a common drive source. Also, to accommodate the production of different size bags, the machine includes a programmable control system, an optical mark sensor, and an adjustable film path length. Further, the machine and method of the present invention ensures reliable seals along the edges of each product-filled bag by having the zipper drive rollers and a bag grabber mechanism stretch the bag material prior to squeezing the excess air out of the product-filled tube and then cross-sealing and severing the bag material. The machine includes a bag squeezer unit having opposing squeeze plates or pads for removing excess air and/or compacting the product to form a reduced size, recloseable bag.

Claims

1. A vertical, form, fill, and seal apparatus of the type that operates in conjunction with a product supply apparatus providing product in discrete quantities and that forms a continuous, heat sealable plastic film and zipper strip into separate product filled, reclosable, sealed bags comprising:

a first controlled release festooner arrangement for storing and supplying a continuous plastic film,

a second controlled release festooner arrangement for storing and supplying a continuous, plastic, zippered cap strip,

a generally vertical fill tube assembly including a vertical fill tube downstream of the first and second festooner arrangements for the continuous film and zippered cap strip and around which the continuous film is formed and wrapped,

feeding means including a plastic film drive roll, a pair of pull belts, and a pair of zippered cap strip drive rollers for feeding the zippered cap strip and plastic film along the length of the vertical fill tube in bag length increments with edges of the plastic film in overlapping relationship with edges of the zippered cap strip,

vertical sealing means for sealing the edges of the plastic film to the edges of the zippered cap strip to form a length of flexible, plastic tube,

a pinch seal assembly downstream of the vertical fill tube for forming first and second horizontal seals across the flexible plastic tube and for severing the plastic tube, the first horizontal seal defining the downstream edge of a bag about to be filled with product and the second horizontal seal defining the upstream edge of a bag which has already received product,

tensioning means for horizontally elongating the plastic tube transverse to its length prior to severing and formation of said first and second horizontal seals, and

a bag squeezer unit downstream of said pinch seal assembly having opposing rigid, planar, squeeze plates and means for reciprocating the plates toward and away from one another along a common axis for selectively contacting flat inner surfaces of each of the plates with the sides of the product filled, flexible, plastic tube and squeezing excess air from the product filled flexible, plastic tube prior to formation of said second horizontal seal and for sequentially releasing each completed, reclosable, product-filled sealed bag following formation of the second horizontal seal and severing of the bag from the flexible tube.

2. Apparatus as recited in claim 1 further comprising tensioning means for horizontally elongating the plastic tube transverse to its length prior to the removal of excess air and formation of said horizontal seals.

3. Apparatus as recited in claim 1 wherein said squeeze plates are removable and mounted to respective reciprocating cantilever means for selectively moving said squeeze plates toward one another to squeeze the product-filled plastic tube therebetween.

4. Apparatus as recited in claim 3 wherein said cantilever means are reciprocated by a single crank rotary actuator assembly.

5. Apparatus as recited in claim 1 wherein said pinch seal assembly and said squeezer unit are each independent of one another and selectively actuated during bag formation.

6. Apparatus as recited in claim 1 further comprising an optical sensor located upstream of said vertical fill tube for sensing registration marks on said plastic film.

7. A vertical, form, fill, and seal apparatus of the type that operates in conjunction with a product supply apparatus providing product in discrete quantities and that forms a continuous, heat sealable plastic film into separate product-filled sealed bags comprising:

first means for storing and supplying a continuous plastic film,

second means for storing and supplying a continuous, plastic, cap strip,

a generally vertical fill tube assembly including a vertical fill tube downstream of said first means for the plastic film, said vertical fill tube being a tube of oval horizontal cross section and means for forming said plastic film around said vertical fill tube with edges of said plastic film meeting at one end of a major diameter of said tube,

feeding means including a plastic film drive roll, a pair of pull belts, and a pair of cap strip drive rollers for feeding the cap strip and plastic film along the length of said vertical fill tube in bag length increments with the edges of the continuous film in overlapping relationship with edges of the cap strip,

vertical sealing means for sealing the edges of the plastic film to the edges of the cap strip to form a length of flexible, plastic tube,

each of said pair of pull belts being mounted on a respective side of the vertical fill tube and biased against the plastic film and said vertical fill tube,

horizontal sealing and severing means downstream of said vertical fill tube for severing the plastic tube and forming first and second horizontal seals across the plastic tube, the first horizontal seal defining the downstream edge of a bag about to be filled with product and the second horizontal seal defining the upstream edge of a bag which has already received product,

tensioning means for horizontally elongating the plastic tube transverse to its length prior to severing and formation of said first and second horizontal seals, and

squeezing means including a pair of opposing removable, rigid, planar squeeze plates operatively connected to a rotary actuator assembly for selective reciprocation toward and away from said plastic tube for contacting flat inner surfaces of each of the plates with the sides of the plastic tube to remove excess air from the product-filled plastic tube prior to formation of said horizontal seals.

8. Apparatus as recited in claim 7 wherein said tensioning means includes said cap strip drive rollers and an opposing rod extending downwardly from said vertical fill tube.

9. Apparatus as recited in claim 7 wherein said squeezing means and said horizontal sealing and severing means include separate independent reciprocation means and are mounted for separate and independent reciprocation toward and away from said plastic tube.

10. A vertical, form, fill, and seal apparatus of the type that operates in conjunction with a product supply apparatus providing product in discrete quantities and that forms a continuous, heat sealable plastic film and zippered cap strip into separate product-filled, reclosable, sealed bags comprising:

means for storing and supplying the continuous plastic film,

means for storing and supplying the continuous, plastic, zippered cap strip,

a generally vertical fill tube assembly including a vertical fill tube downstream of the means for storing and supplying the continuous film and around which the continuous film is formed and wrapped,

feeding means for feeding the continuous zippered cap strip and plastic film along the length of the vertical fill tube in bag length increments with edges of the continuous film in overlapping relationship with edges of the zippered cap strip,

vertical sealing means for sealing the edges of the continuous film to the edges of the continuous zippered cap strip to form a flexible, plastic tube,

horizontal sealing and severing means downstream of the vertical fill tube for forming upper and lower horizontal seals across the flexible plastic tube and for severing the plastic tube,

tensioning means for horizontally elongating the flexible, plastic tube transverse to its length prior to formation of said horizontal seals,

bag squeezer means including a pair of opposing removable, rigid, planar squeeze plates operatively connected to a rotary actuator assembly for selective reciprocation toward and away from said plastic tube for contacting flat inner surfaces of each of the plates with the sides of the plastic tube to squeeze the excess air from the product-filled plastic tube following horizontal tensioning of said plastic tube and prior to formation of said upper horizontal seal, and

bag support means for sequentially supporting each product-filled bag during formation of said horizontal seals and releasing each completed, reclosable, product-filled, sealed bag following severing of the bag from the flexible tube.

11. In a vertical, form, fill and seal apparatus including a vertical fill tube and horizontal sealing means and of the type that forms a continuous, heat sealable plastic film and a continuous plastic zippered cap strip into a flexible tube, a three-sided partially formed product-filled bag and then into a four-sided separate, reclosable, product-filled sealed bag, the improvement comprising:

tensioning means for horizontally elongating the plastic tube transverse to its length prior to severing and formation of horizontal seals, and

a bag squeezer unit located downstream of said horizontal sealing means and including opposing, planar squeeze plates operatively connected to a rotary actuator assembly for selectively driving said squeeze plates toward and away from said partially formed product-filled bag along a common axis to contact flat inner surfaces of each of the plates with the sides of the partially formed product-filled bag to remove excess air from said partially formed product-filled bag prior to completion of said bag.

12. The apparatus as recited in claim 11 wherein said squeeze plates are sized and positioned so as to contact a substantial portion of each bag.

13. The apparatus as recited in claim 11 wherein said squeeze plates are substantially rigid.

14. The apparatus as recited in claim 11 wherein each of said squeeze plates has a resilient inner surface for contacting each bag.

16. The apparatus as recited in claim 11 wherein said squeeze plates are removable to provide for the replacement thereof or the use of different plates to accommodate at least one of different size bags, different types of product, different amounts of product, and different bag materials.

15. In a vertical, form, fill and seal apparatus including a vertical fill tube and horizontal sealing means and of the type that forms a continuous, heat sealable plastic film and a continuous plastic zippered cap strip into a flexible tube, a three-sided partially formed product-filled bag and then into a four-sided separate, reclosable, product-filled sealed bag, the improvement comprising:

a bag squeezer unit located downstream of said horizontal sealing means and including opposing, planar squeeze plates having rigid, shaped, squeeze pads attached to the inner surface of each of the squeeze plates, and means for selectively driving said squeeze plates toward and away from said partially formed product-filled bag along a common axis to contact inner surfaces of each of the squeeze pads with the sides of the partially formed product-filled bag to remove excess air from said partially formed product-filled bag prior to completion of said bag, wherein the rigid, shaped, squeeze pads facilitate the removal of excess air and selectively compact the product in each bag.

17. In a vertical, form, fill and seal apparatus including a vertical fill tube and of the type that forms a continuous, heat sealable plastic film into a flexible tube and then into separate sealed bags, the improvement comprising:

tensioning means for horizontally elongating the flexible tube transverse to its length prior to severing and formation of horizontal seals, and

at least one pair of opposing, rigid planar squeeze plates located downstream of the vertical fill tube with the flexible tube therebetween and mounted to a rotary actuator assembly for controllable reciprocation along a common axis to contact rigid, flat inner surfaces of each of the plates with the sides of the flexible tube to squeeze the sides of the flexible tube therebetween to remove excess air therein prior to completion of said sealed bags.

18. In a method of forming separate, product-filled, reclosable bags from a heat sealable plastic film and zipper which form a plastic tube, the improvement comprising:

horizontally elongating the plastic tube transverse to its length prior to severing and formation of seals using tensioning means, and

squeezing the excess air from each product-filled bag prior to final formation thereof using a pair of opposing, rigid, planar squeeze plates mounted to a rotary actuator assembly and having flat inner surfaces which are brought into contact with the sides of the bag to remove excess air therefrom and at least partially compact the product therein.

19. In a vertical, form, fill and seal apparatus including a vertical fill tube and of the type that forms a continuous, heat sealable plastic film into a flexible tube and then into separate sealed bags, the improvement comprising:

at least one pair of opposing, rigid planar squeeze plates located downstream of the vertical fill tube with the flexible tube therebetween, and mounted for controllable reciprocation along a common axis, and with respective rigid, shaped, squeeze pads attached to the inner surface of each of said squeeze plates and with contoured inner surfaces in position to contact the sides of the flexible tube to squeeze the sides of the flexible tube therebetween to remove excess air therein prior to completion of said sealed bags.

20. A vertical, form, fill, and seal apparatus of the type that operates in conjunction with a product supply apparatus providing product in discrete quantities and that forms a continuous, heat sealable plastic film into separate product-filled sealed bags comprising:

first means for storing and supplying a continuous plastic film,

second means for storing and supplying a continuous, plastic, cap strip,

a generally vertical fill tube assembly including a vertical fill tube downstream of said first means for the plastic film, said vertical fill tube being a tube of oval horizontal cross section and means for forming said plastic film around said vertical fill tube with edges of said plastic film meeting at one end of a major diameter of said tube,

feeding means including a plastic film drive roll, a pair of pull belts, and a pair of cap strip drive rollers for feeding the cap strip and plastic film along the length of said vertical fill tube in bag length increments with the edges of the continuous film in overlapping relationship with edges of the cap strip,

vertical sealing means for sealing the edges of the plastic film to the edges of the cap strip to form a length of flexible, plastic tube,

each of said pair of pull belts being mounted on a respective side of the vertical fill tube and biased against the plastic film and said vertical fill tube,

horizontal sealing and severing means downstream of said vertical fill tube for severing the plastic tube and forming first and second horizontal seals across the plastic tube, the first horizontal seal defining the downstream edge of a bag about to be filled with product and the second horizontal seal defining the upstream edge of a bag which has already received product,

tensioning means for horizontally elongating the plastic tube transverse to its length prior to severing and formation of said first and second horizontal seals,

squeezing means including a pair of opposing removable squeeze plates operatively connected to a rotary actuator assembly for selective reciprocation toward and away from said plastic tube for contacting the sides of the plastic tube to remove excess air from the product-filled plastic tube prior to formation of said horizontal seals,

wherein said tensioning means includes said cap strip drive rollers and an opposing rod extending downwardly from said vertical fill tube, and

wherein said tensioning means further includes bag grabber means comprising a pair of opposing air cylinder units located downstream of said horizontal sealing and severing means for selectively clamping said plastic tube therebetween.

21. A vertical, form, fill, and seal apparatus of the type that operates in conjunction with a product supply apparatus providing product in discrete quantities and that forms a continuous, heat sealable plastic film and zipper strip into separate product filled, reclosable, sealed bags comprising:

a first controlled release festooner arrangement for storing and supplying a continuous plastic film,

a second controlled release festooner arrangement for storing and supplying a continuous, plastic, zippered cap strip,

a generally vertical fill tube assembly including a vertical fill tube downstream of the first and second festooner arrangements for the continuous film and zippered cap strip and around which the continuous film is formed and wrapped,

feeding means for feeding the zippered cap strip and plastic film along the length of the vertical fill tube in bag length increments with edges of the plastic film in overlapping relationship with edges of the zippered cap strip,

vertical sealing means for sealing the edges of the plastic film to the edges of the zippered cap strip to form a length of flexible, plastic tube,

a pinch seal assembly downstream of the vertical fill tube for forming first and second horizontal seals across the flexible plastic tube and for severing the plastic tube, the first horizontal seal defining the downstream edge of a bag about to be filled with product and the second horizontal seal defining the upstream edge of a bag which has already received product,

a bag squeezer unit downstream of said pinch seal assembly having opposing planar, squeeze plates and means for reciprocating the plates toward and away from one another along a common axis for contacting the sides of and squeezing the excess air from the product filled flexible, plastic tube prior to formation of said second horizontal seal and for sequentially releasing each completed, reclosable, product-filled sealed bag following formation of the second horizontal seal and severing of the bag from the flexible tube, and

tensioning means including cap strip drive rollers and an opposing rod extending downwardly from said vertical fill tube, and bag grabber means comprising a pair of opposing air cylinder units located downstream of said pinch seal assembly for selectively clamping said plastic tube therebetween.

22. In a vertical, form, fill and seal apparatus including a vertical fill tube and of the type that forms a continuous, heat sealable plastic film into a flexible tube and then into separate sealed bags, the improvement comprising:

flexible tube tensioning means including an opposing rod extending downwardly from said vertical fill tube, and bag grabber means comprising a pair of opposing air cylinder units located on opposite sides of the flexible tube downstream of said vertical fill tube for selectively clamping said flexible tube therebetween, and

squeezing means including a pair of opposing removable, rigid, planar squeeze plates operatively connected to a rotary actuator assembly for selective reciprocation toward and away from said flexible tube for contacting flat inner surfaces of each of the plates with the sides of the flexible tube to remove excess air from the product-filled flexible tube prior to formation of horizontal seals.